DEVELOPMENT OF SMOKELESS NON-TOXIC GAS GENERATINGCOMPOSITIONS FOR AUTOMOBILE AIRBAG INFLATORS

摘要

Theoretical investigations of combustion temperature regularities of stoichiometric CHNO-compositions depending on formation enthalpies, elemental formulation and pressure have been performed. Algorithm of the user's program has been created, which could find compositions with the desired combustion temperature from the database of available components. It has been shown that stoichiometric CHNO-compositions with combustion temperature 2400-2500K at 200 atm can be created on the base of ammonium nitrate only. More than 36 new organic compounds, which could become components for gas generating compositions, have been first synthesized, new methods of synthesis have been developed Phase transformations of ammonium nitrate were examined, and in many cases an intermediate roentgen-amorphous phase was shown to form during the phase transition. Methods for phase stabilization of ammonium nitrate were found, which provide the presence of only two (II and IV at about 50°C), not four phase states in the temperature range –50 to +100°C. Thermal stability and impact sensitivity of new chemical compounds was studied, as well as compatibility of ammonium nitrate with other components. A range of organic compounds compatible with ammonium nitrate was found. Thermal stability of some obtained compounds is rather high - during two-weeks exposition at +110 °C the decomposition level is not much higher than 1%, so there is a hope for their stabilization and possibility to use them in gas generating compositions. Main regularities of thermal stability for compounds containing nitrogroups together with low-enthalpy oxygen-containing groups were found. Regularities of charges combustion depending on different factors (catalyst, presence of high energetic components, modes of the charge formation, etc) have been studied. It was shown that burning rates of ammonium nitrate based compositions can be raised many times by formation of a special porous structure of the charge. Different ways of such structures formation were studied.